Satellite broadcasting system and signal receiving method thereof

Abstract

Provided is a satellite broadcasting terminals. The satellite broadcasting terminal includes: a first antenna receiving a radio signal of a first band or a second band; a second antenna receiving a radio signal of a third band; a first stream demodulating unit demodulating a first stream signal received through the first band; a second stream demodulating unit demodulating a second stream signal received through the second band; a playing unit playing the demodulated first or second stream signal; and a gap filler receiving unit selectively providing the first stream signal to the first stream demodulating unit in response to a radio signal intensity of the third band, the first stream signal being received through the third band.

1 . A satellite broadcasting terminal comprising:
 a first antenna receiving a radio signal of a first band or a second band;   a second antenna receiving a radio signal of a third band;   a first stream demodulating unit demodulating a first stream signal received through the first band;   a second stream demodulating unit demodulating a second stream signal received through the second band;   a playing unit playing the demodulated first or second stream signal; and   a gap filler receiving unit selectively providing the first stream signal to the first stream demodulating unit in response to a radio signal intensity of the third band, the first stream signal being received through the third band.   
   
   
       2 . The satellite broadcasting terminal of  claim 1 , wherein the gap filler receiving unit comprises:
 a first receiving module converting the first stream signal, which is received through the second antenna, into a baseband signal and delivering the converted baseband signal to the first stream demodulating unit;   a signal intensity detecting element detecting the radio signal intensity of the third band received through the second antenna; and   a switch controlling element delivering a switch control signal to the first stream demodulating unit according to an intensity of the radio signal, the switch control signal selecting a path of the first stream signal.   
   
   
       3 . The satellite broadcasting terminal of  claim 2 , wherein the first stream demodulating unit comprises:
 a second receiving module converting the first stream signal to a baseband signal, the first stream signal being received through the first antenna; and   a switch allowing selectively one of the first receiving module and the second receiving module to receive the first stream signal in response to the switch control signal.   
   
   
       4 . The satellite broadcasting terminal of  claim 3 , wherein the first stream demodulating unit comprises:
 a first demodulating module demodulating the first stream signal of the baseband into a digital signal, the first stream signal being supplied through the switch;   a first decoding module decoding an output of the first demodulating module; and   a first mode and stream counter adaptation module restoring a deleted null-packet and an MPEG2-TS packet header in data decoded through the first decoding module in order to constitute an original MPEG2-TS stream.   
   
   
       5 . The satellite broadcasting terminal of  claim 4 , wherein the second stream demodulating unit comprises:
 a third receiving module converting the second stream signal into a baseband signal, the second stream signal being received from the first antenna;   a second demodulating module demodulating the first stream signal from the third receiving module into a digital signal;   a second decoding module decoding an output of the second demodulating module; and   a second mode and counter adaptation module restoring a deleted null-packet and an MPEG2-TS packet header in data decoded through the second decoding module in order to constitute an original MPEG2-TS stream.   
   
   
       6 . The satellite broadcasting terminal of  claim 1 , wherein the first band is a Ku-band and the second band is a Ka-band. 
   
   
       7 . The satellite broadcasting terminal of  claim 1 , wherein the third band is an industrial, scientific, and medical (ISM)-band, wherein a gap filler receives and frequency-converts the first stream signal transmitted through the first band and retransmits the frequency-converted first stream signal through the ISM-band. 
   
   
       8 . The satellite broadcasting terminal of  claim 1 , wherein the first stream signal has a higher priority than the second stream signal. 
   
   
       9 . The satellite broadcasting terminal of  claim 1 , wherein the playing unit selectively plays one of an SD video signal through the first stream signal and an HD video signal through the combined first and second stream signals. 
   
   
       10 . A broadcasting signal receiving method of a satellite broadcasting system, the method comprising:
 measuring an intensity of a radio signal transmitted from a gap filler; and   receiving a broadcasting signal by selectively linking with one of the gap filler and a broadcasting satellite in response to the intensity of the radio signal,   wherein the satellite broadcasting system transmits broadcasting signals of a plurality of hierarchical layers through respectively different bands.   
   
   
       11 . The method of  claim 10 , wherein the gap filler is linked when the intensity of the radio signal is higher than a reference reception intensity and the broadcasting satellite is linked when the intensity of the radio signal is identical to or lower than the reference reception intensity. 
   
   
       12 . The method of  claim 11 , wherein a first stream signal of a high priority is transmitted through the gap filler. 
   
   
       13 . The method of  claim 12 , wherein when the broadcasting satellite is linked, the first stream signal and a second stream signal having a lower priority than the first stream signal are received through the respectively different bands. 
   
   
       14 . The method of  claim 11 , wherein the gap filler frequency-converts the first stream signal received from the broadcasting satellite and transmits the frequency-converted first stream signal through an ISM-band. 
   
   
       15 . The method of  claim 11 , wherein the broadcasting satellite transmits the first stream signal through a Ku-band and transmits the second stream signal through a Ka-band.